1. Field of the Invention
The present general inventive concept relates to an image forming apparatus having a hybrid inkjet head and an inkjet head wiping device, and more particularly, to an image forming apparatus having a hybrid inkjet head and an inkjet head wiping device capable of performing both high-speed printing and high-resolution printing.
2. Description of the Related Art
An inkjet printer ejects fine ink droplets onto a desired position of a printing medium (e.g., paper or textile) to print an image of a predetermined color on a surface of the printing medium.
The inkjet printer has an inkjet head printing the image onto paper while performing a reciprocating motion in a direction (i.e., a width direction of the paper) perpendicular to a medium delivery direction of the paper. Such an inkjet printer is called an inkjet printer having a shuttle type inkjet head. The inkjet printer having a shuttle type inkjet head that prints the image while performing the reciprocating motion has high resolution but has a disadvantage of a slow printing speed.
Recently, an inkjet printer capable of printing an image in a high speed onto paper delivered in a stationary state without the reciprocating motion of an inkjet head by adopting an inkjet head array having a plurality of printheads disposed over the entire width of the paper, has been developed. Such an inkjet printer is also called an inkjet printer having an array type inkjet head. The inkjet printer has a high printing speed but has a disadvantage of low resolution.
The array type inkjet heads eject fine ink droplets onto a desired position of the paper. Also, the inkjet heads use thermal energy or a piezoelectric element as an ink ejection driving source.
A nozzle unit disposed on each inkjet head fires ink onto the paper. After printing is completed, residual ink or foreign substance left (remaining) after firing of the ink is performed is attached on a surface of the nozzle unit of the inkjet head. Since the residual ink or the foreign substance adheres to holes of the nozzle unit as time elapses, a nozzle malfunction where ink droplets are not fired when printing is performed may be generated, or a firing direction of the ink droplets may be deflected and thus an impact position of the ink droplets may be out of an exact position. Therefore, the inkjet image forming apparatus having the inkjet heads includes a wiping element that wipes out the residual ink or foreign substance stuck on the surface of the nozzle unit so as to maintain the surface of the nozzle unit clean. Also, the inkjet image forming apparatus includes a spitting element that fires ink to remove the foreign substance disposed in holes of the nozzle unit so as to maintain the nozzle unit blocking-free and a capping element that covers the nozzle unit when the image forming apparatus is in a standby state to prevent drying of ink and protect the nozzle unit from external foreign substance.
The above-described wiping element, spitting element, and capping element are commonly called a maintenance element. To manufacture a small-sized inkjet image forming apparatus, a small-sized and light-weight maintenance element is required.
Since a shuttle type inkjet printer has a small inkjet head, a problem is not particularly generated in connection with installation of the maintenance element. However, an array type inkjet head having a nozzle unit of a length that corresponds to the width of the paper and printing an image while delivering paper in a length direction of paper has a relatively long width. Accordingly, a space in which the maintenance element is installed is relatively wide. That is, when a predetermined maintenance operation is performed for the array type inkjet head, the inkjet head does not move to a maintenance region, and instead, the wiping element, spitting element, and capping element move, by turns, to the nozzle unit whose position is fixed.
Here, the wiping element has a wiper unit wiping out the residual ink on the surface of the nozzle unit and a wiper unit driving element that reciprocates the wiper unit in a wiping direction.
Therefore, in the inkjet printer having the array type inkjet head, it is difficult to reduce an installation space of the wiping element and a drive mechanism of the wiping element.